Boiler-plug.



A. c. LIPPINCOTT BOILER PLUG. APPLICATION FILED MAY I5. I9IB.

Patented Nov. 26, 1918.

9 NORA/E78 UNITED STATES PATENT OFFICE.

ALPHEUS C. LIPPINCOTT, OF EAST ORANGE, NEW JERSEY, ASSIGNOR TO E KEELER COMPANY, OF WILLIAMSPORT, PENNSYLVANIA, A CORPORATION OF PENNSYL- .VANIA.

BOILER-PLUG.

Specification of Letters Patent.

Patented Nov. 26, 1918.

To all whom it may concern:

Be it known that I, ALPHEUs C. LIPPIN- coTT, a citizen of the United States, residing in the city of East Orange, county of Essex, and State of New Jersey, have invented certain new and useful Improvements in Boiler- Plugs, of which the following is a specification. a

The invention relates in general to a sealing device for hermetically closing holes in the apertured walls of pressure confining vessels and the like, and specifically relates to an improvement in boiler plugs of the rolled-in type usually employed in closing the hand hole, the man-hole and similar openings in boiler elements.

In boiler construction it has been known to insert a closed end plug in the hand holes usually with a tapered fit, and by means of a'rolling tool the tapered side of the plug is expanded outwardly into a fitting engage ment with the outlining edge of the hand hole. When in active operation boilers not only have a high internal pressure, frequently as high as three hundred and fifty pounds per square inch, but this pressure varies from time to time creating the objectionable breathing or pulsating action of the several parts. Where this breathing action occurs in boilers equipped with the known types ofboiler plugs, it tends to work the hand hole sheets back and forth across their normal planes thus tending to loosen the connection between the edges of the hand holes and the plugs. Further the pres sure acting during this time on the closed ends of the lug not only forces the tapered portion of t e plug on to the seat provided by the outlining edges of the hand hole but goes farther, and tends to squeeze the plug bodily through the hand hole. -Both of these agencies coact eventually in causing a leakage to develop between the plug and its seat, especially after the plug has been in use for a long time.

Accordingly, one of the objects of the invention is to provide -a simple form of plug of the type described, in which the ro ledin portion engaging the seat provided by the edge of the hole may be permanently fixed in sealing engagement with the seat, unaffected by the breathing action of the hand hole sheet and in which the pressurereceiving, closed, head end will be designed to defeat any tendency of repeated abnormal high pressure conditions to cause a leakage past the plug.

Broadly, this object is attained by providin a hollow mushroom-shaped plug with a cylindrical neck having a fit in the hole but not necessarily a sealing fit and with an enlarged springy head, the periphery of which is designed to have a sealing engagement with the portion of the sheet surrounding the hole.

Another object of the inventionfor usethe following particular description of one form of mechanism embodying my invention, and the invention also consists in certain new and novel features of construction and combination of parts hereinafter set forth and claimed.

In the accompanying drawings:

Figure 1 is a fragmentary view in section through a boiler element showing a preferred embodiment of my invention in position thereon and with parts broken away to show one form of joint;

Fig. 2 is a similar view showing a second form of the invention in axial section; and both figures coact to illustrate a vertical sectional view through the upper portion of a boiler head and showing two ways of utilizing the plug forming the common element in both illustrated forms of closures.

In the following description and in the claims parts will be identified by specific names for convenience of expression but they are intended to be as generic in their application to similar parts as the art will permit, for instancethe word sheet indicates any form of apertured member and hole or hand hole indicates any form of opening through such member.

In the drawings there is illustrated collectively in the two views a part of a boiler water leg formed of a tube sheet 10, and hand hole sheet 11 connected by a wrapper sheet 12 and coacting to form a pressure chamber 13 designed to contain a Variable high pressure. /Vater tubes let terminate at the tube sheet and opposite each tube the hand hole sheet is provided with a hand hole 15 all as is usual with well known types of such boiler constructions.

Referringparticularly to the form of the invention illustrated in Fig. 1, there is shown a hollow thin walled metallic mushroom shaped plug 16 for closing the hand hole 15. The plug includes an expansihle tubular neck 17 constructed to have a loose or at most, a driving-tight lit in the hole 15 and preferably projecting slightly beyond opposite ends of the hole. The end of the neck in the chamber 13 is provided with an enlarged hollow head 18' somewhat fiattened from the segment of prolate ellipsoid and having a diameter materially greater than the diameter of the hand. hole.

The central ellipsoidal portion of the head forms a pressure receiving springy wall 19 forming an intensive area 0'? surface or posed to the pressure in the chaniher 13. The wall 19 rounds sharply into a ring shaped hearing member "20 facing the portion 21 ot' the sheet 11 surrounding the hole 15. The bearing member 20 extends almost at right angles to the axis of the tubular neck 17 and on its inner side coacts with the neck to form an internal shouldered peripheral bearing surface 22 adapted to be engaged by an extension of an expanding tool to hold the plug in place against the portion 2i during the process of expanding the neck into sealing engagement with the edge 23 ot the hole 15.

Instead of the ring member 20 extending strictly parallel to the portion 2L it is: shown slightly inclined from its inner periphery at the neck, out ardly toward its outer periphery which in Fig. l is in bearing engagement with the portion 21 of the sheet. 1 is to he understood however, that the showing of this incline has been greatly eragzgerated in Fig. 1 so as to show clearly the effect of high pressure. in this desire the closure is illustrated in its simplest form huiit is intended. especially where high pressure conditions are present in the chamber id to insert a ring: gasket, 2%. shown in hr. 2} between the member 20 and the portiCl l of the shelh as an additional safe guard,

, 1 me in ad may desired distance thus providing for any desired security against leakage.

In the form of the invention illustrated in .liig. l the plug is intended to he secured perr-aianently in place by the frictional tight fit between the neck and the edge 23 While cued to engage the plug is recessed to ered bearing surtace i2 so as to center eper across the opening 15, and to lie a circular bearing tor engaging the of "he surface 20 opposite the gasket 24. conventional form is bridged across the hole 15 and engages the side of i sheet 11 opposite the head 16. drawing: member 28 in the i i'irni of headed bolt 1 passed through the center of the spider and has its headed end 9" inserted in a bifurrated 0 tension 30 preyect from the front vce of the keeper and adjacent its center. 7 nut 31 is threaded on the outer end of the hoit and bears on the 'der to draw the he per toward the sheet ii and into position to act through the surface 20 thereby to compr ss the gasket as preriously described ction with the sho in in Fig. 1.

actual practice sometimes happens at there a variation the diameters of and holes which in some cases would require an excessive ex anding of the neck to obtain a fit, l to tak-i up this d the oresent shape oi the neck and .1 race is designed in the torn'i pronounced reentrant angle or rather curre of small radius i .e angle oeas shown at in Fig. i The effect enlarging the irneter r is simply particularly portions 1 hand holes ageme action kid nection is desired. Especially where a gasket is interposed between the plug head and the sheet, a form of rolling tool is used which can engage the bearing surface 20"to hold the head in gasket-compressing position while the neck is being expanded into position. Without the gasket the plug head is moved forwardly into such an engagement with the sheet that the outer periphery is in light bearing engagement with the portion 21, thus providing two sealing lines, one at the neck and the other near the periphery of the head.

With increase of temperature in the chamber 13, the wall 19 will tend to expand, and increase of ressure in the chamber will tend to flatten t e wall both of which actions of the wall will move the outer periphery of the head more firmly into bearin engagement with the sheet, or when a gas et is employed, into position to more firmly compress the gasket.

By this means, with the increased action of those agencies which cause leakage, there will be an increased sealing to defeat any tendency toward leakage. The movement of the periphery of the head will tend to minimize, if not eliminate, an tendency of the neck to creep in the hen hole, thus maintaining a permanency of the sealing jointat this place. In other words, a feature of this connection is to hold the neck in place and to divert pressure actions away from the neck.

Increased ressure on the head of the plug acts not to Orce-it through the hand hole but to flatten the periphery of the head into firm binding engagement against the portion of the sheet surrounding the hole. As the diameter of the hand hole reduces during the contraction of the sheet on cooling, the wall 19 of the head simply bellies outwardly into the chamber 13 thus providing for flexibility in the connection between the plug and sheet. I

In the form'shown in Fig. 2 it is understood that the neck may be rolled in to position as previously described but this is not necessary and a loose or driving fit is sufficient.

The plug with the ring gasket in position about the neck, is inserted in position 'with the neck extending through the hand hole. The keeper is either carried by the plug head or is inserted into place after the plug is mounted in the hand hole. As the keeper is positioned across the inner end of the neck it tends to resist any tendency of the pressure to collapse the inner end of the neck. Also this keeper acts to hold the inner periphery of the ring-gasket, thus assisting to coact with the action of the surface 20 in compressing the outer periphery of the ring as hereinbefore described.

The bolt head is inserted in the bifurcated projection, the spider is inserted over the bolt and the bolt nut is drawn up into tight engagement with the spider.

In this way the pull of the bolt acts centrally on the keeper to draw the same uniformly against practically the entire circumference of the bearing surface 22.

Should it be desired to demount the plug temporarily, the spider is demounted and b means of a hook tool engaging in the peripheral recess formed by the member 22- and' wall 19, the plug, with the keeper therein, can be displaced into the chamber 13 and afterward re-inserted in place. The spider yoke can then be replaced and the parts are again in operative position.

While one form of the plug has been described as formed with the periphery of the bearing member 20- disposed close to the sheet, it will be understood that even though the plug is not so formed, still the pressure on the head will tend to move the periphery toward and into engagement with the sheet without movement of the neck.

While I have shown and described, and

.have ointed out in the annexed claims certain novel features of my invention, it will be understood that various omissions, substitutions and changes in the form and details of the device illustrated and in its operation may be made by those skilled in the art without departing from the spirit of the invention.

Having thus describ'ed my invention, I claim 1. 'In a device of the class described, the combination with a sheet subject to a pressure on one side thereof and provided with a hole extending therethrough, of a hollow mushroom shaped plug including a neck fitted in said hole and having a head on the pressure-exposed side of said sheet, the peripheral part of said head bein double walled with the walls substantial y paralleling the sheet, with the wall adjacent the sheet providing a bearing surface for effecting a seal between the head and the portion .of the sheet surrounding the hole, and the other wall being springy, exposed to the pressure present on the pressure-exposed side of the sheet and acting on said bearing surface to move the same toward the sheet.

2. In a device of the class described, the combination with a sheet subject to a pressure on one side thereof and provided with a hole extending therethrough, of a hollow mushroom shaped plug including a neck fitted in said hole and having a head on the 3. In a device of the class described, the combination with a sheet subject to a pressure on one side thereof and provided with a hole ext-ending therethrough, of a hollow mushroom shaped plug including a neck fitted in. said hole and having a head on the pressure-exposed side of the sheet, the side of the head facing the sheet being hollow and extending substantially at right angles to the neck and constituting a bearing surface for effecting a seal between the head and the portion of the sheet surrounding the hole, the outer edge of said bearing surface being movable toward said portion ungerthe action of the pressure acting on the 4. In a device of the class described, the combination with a sheet provided with a hole extending therethrough, of a plug for closing said hole, said plug including a head provided with a ring shaped bearing surface facing the portion of the sheet surrounding the hole, and including a neck integral with the head and fitted in said hole for spacing the inner periphery of said ring-shaped bearing surface from the sheet, the outer periphery of said bearin surface being free to move relative to said portion to effect a variable sealing between the head of the plug and the sheet.

5. In a device of the class described, the combination with a sheet provided with a hole extending therethrough, of a plug for closing said hole, said plug including a head provided with a ring shaped bearing surface facing the portion of the sheet surrounding the hole, and including a neck integral with the head and fitted in said hole for spacing the inner periphery of said ring-shaped bearing surface from the sheet, the outer periphery of said bearing surface being free to move relative to said portion to effect a variable sealing between the head of the plug and the sheet and a ring gasket fitted between the bearing surface and said portion.

6. In a device of the class described, the combination with a sheet provided with a hole extending therethrough, of a plug for closing said hole. said plug including a head provided with a ring shaped bearing surface facing the portion of the sheet surrounding the hole. and including a neck integral with the head and fitted in said hole for spacing the inner periphery of said ring-shaped bearing surface from the sheet, the outer periphery of said bearing surface being free to move relative to said portion to afiect a variable sealing between the head of the plug and the sheet and said head in cluding pressure receiving means operatively connected with said outer periphery to effect said variable sealing.

7. In a device of the class described, the combination with a sheet provided with a hole extending therethrough, of a plu for closing said hole, said plug including a head provided with a ring shaped bearing surface facing the portion of the sheet surrounding the hole, and includin a neck integral with the head and fitted in said hole for spacing the inner periphery of said ring-shaped bearing surface from the sheet, said ring shaped bearing surface being inclined slightly toward the sheet from its inner periphery outwardly toward its outer h periphery and a gasket disposed in the space formed by said inclined bearing surface and the adjacent portion of the sheet surrounding the hole,

8. In a device of the class described, the combination with a sheet provided with a hole extending therethrough, of a hollow plug for sealing said hole, said plug provided with a neck fitting in the hole and with a head having a diameter greater than the diameter of the hole, said head including interiorly exposed means providing a tool receiving surface adaptedto be engaged by a tool for drawing the head toward the portion of the sheet surrounding the hole in the process of mounting the plug in place.

9. In a device of the class described, the

combination with a sheet provided with a hole extending therethrough, a mushroom shaped hollow plug having a neck fitted in and adapted to be rolled into a sealing fit with the edge portion of the sheet outlining the hole, said plu having a hollow head at one end of the neck and extending outwardly therefrom to lap the side portion of the sheet surrounding the hole, said head including an outlining hollow ring facing the sheet and adapted to receive an extended portion of a neck rolling tool whereby said extended portion can act on the head to draw the same toward the sheet during the act of rolling the neck into engagement with the edge of the hole.

10. As an article of manufacture, a hollow, mushroom shaped boiler plug including an expandable cylindrical and continuous neck and an enlarged head designed to Withstand boiler pressures thereon, said head forming substantially a right-angled external shoulder with the neck, said shoulder constituting a pressure receiving surface.

11. As an article of manufacture, a hollow, mushroom shaped boiler plug including a continuous tubular neck and an enlarged head, said head forming substantially a right-angled external shoulder with the neck, and a ring gasket fitted to said neck and engaging to said external shoulder and designed to be compressed by pressure on said head.

12. In a device of the class described, the combination with a sheet provided with a hole extending therethrough, of a closure including a plug for closing said hole and having a head with an internal diameter greater than the diameter of the hole, a keeper forengaging the interior portion of the head facing the portion of the sheet surrounding the hole and adapted to act thereon to draw the head toward said hole-surrounding-sheet-portion.

13. In a device of the class described, the combination with a sheet provided with a hole extending therethrough, of a closure including a plug for closing said hole and having a head with an internal diameter greater than the diameter of the hole, a keeper for engaging the interior portion of the head facing the portion of the sheet surrounding the hole, said keeper provided with means for centering the same in the head and also provided with means for drawing the head toward the sheet.

14. In a device of the class described, the combination with a sheet provided with a hole extending therethrough, of a plug for closing said hole, said plug including a tubular member fitting in said hole and a member extending outwardly from the tubular member and forming an internal shoulder therewith, a keeper provided with. a peripheral shoulder fitting said internal shoulder and means acting on said keeper for holding the portion of the plug surrounding the hole in position.

15. In a device of the class described, the combination with a sheet provided with a hole extending therethrough, or" a plug for closing said hole, said piugincluding a tubular member fitting in said hole and a member sitioned on one side of the sheet and its neck fitted in said hole, a spider bridged across the hole on the opposite side of the sheet, a keeper positioned within the head and engaging the side thereof disposed opposite the sheet and bolt connecting the keeper and spider and a gasket disposed between the head of the plug and the adjacent side of the sheet, said gasket designed to be compressed by the tightening up of said bolt.

17. In a device of the class described, the combination of a sheet provided with a hand hole, a mushroom shaped plug having a neck fitted in said hole and immovable relative thereto, the periphery of the head of said plug being resilient and adapted to be acted upon by the pressure onsaid head to force the same toward said sheet.

Signed at New York, in the county of New York and State of New York, this 8th day of May, A. D. 1918.

nilrinnus o. LIPPINCOTT. 

